Undercutting-saw support



14 1927. June A. DAHLMAN UNDERCUTTING SAW SUPPORT Filed June 30, 1926 MIIV F IIIH I' 11 Patented June "14,1927. t v

1 ALFRED DAiILMAN, or nirrnnjonneon.

:ggf I UnnERoUrrmG-siiw SUPPORT."

' Application fi1ed .Tune so, 1926. Serial No. 119,614.

v. This invention relates to apparatus for est supporting cross-cut saws in undercut sawingoperations. t j

The object. of the invention is the provision of an. undercutting support for saws,

of simple and economical construction, having a clamping device for the swingajble supporting arm thereof which is easily and quicklyoperated to change said arm to a ny angle of adjustment, and which .is positive and secure in itsrclamping action.

Other objects and advantages of my in vention, andiobiects relating to details of 1 construction, will be readily apparent. in the course of the detailed description to follow.

The accompanying drawings illustrate by way of example a preferred form of my invention, in which: Figural is a view inside elevation of an embodiment of my invention.

' Fig. 2 is a plan view of the same. Fig. 3 is a fragmentary view in vertical section on line3-3 of Fig. 2.

Referring to said views, the reference numeral 1 indicates a steel bar, desirably of squared cross-section, having a driving point 2 at one end and a driving head 3 at the other. A slide block 5 is provided for said bar formed with a middle portion 6 and two parallel ears 7 spaced apart, between which the bar 1' may be received. Said ears are formed with aligned apertures v centrally adjacent their outer ends.

-An arm 8 formed of a circular metal rod extends in parallel with the bar 1 and is formed with a right-angled extremity 10 whichexte'nds' through theear apertures and is secured therein. by cotter-pins 11 extending through holes in said extremity exterior of the ears, respectively. At the opposite end of said arni it isfsimilarly formed with a right-angular extremity 12 upon which a cylindrical saw support 13 is rotatively mountedv andmay be secured' thereon by cotter-pins 15. V 1 I "The support 13 is formed about its periphery with a pluralityof circulargrooves 16 extending in parallel planes with the bar 1. r

A clampinglever 17 is formed integrally with a cam head '18 of symmetrically curved configuration relative to the longitudinal axis of said lever and is provided with an aperture 20 of approximately the same diaper'tnre 20 is located in the extended 1on aineter as the apertures in the earsv 7 The gitudinal axis of th-elever and eccentrically with regard to the outer curvedor circular 7 end of the head 18, whereby the' distanc'es between the center of the aperture20 (and the periphery of said head in transverse lines is less than the distance between said 1 1, is'formed with a boss 21 having a screwthreaded'bore "therein through which ex-; tends a' clamping'screw 22 provided with a craillk end 23 by which it may be manipu- The head 18 extends between the ears and. bears upon the bar 1 with itslateral side face. The extremitylOofthe rod 8 passes through the aperture 20 as well as the apertures in the ears upon each side.

With the apparatus assembled in operative position as described, the point 2of the bar may be driven into the log which'is to be undercut, either horizontally or in any other preferred d rection, to securely fix it to bear the weight of the saw and the force of driving the saw in the Work to be performed.

The arm 8 is then swung about its axis in the arm 7 to bring the supporting roller 13 into "proper distance and suitable relation with respectto thelog.

When the clamp 22 is loosened this arm 8 may be freely swung ,to any position, and, when set, may be readily and quickly tightened and clamped firmly by the manipulation of the screw 22 extending. through the clamp lever -17 andbearing upon the bar 1 whereby the lever is forced upwardly at its outer end, which tends to swing the aperture 20 out of register with the ear apertures, due to the eccentricity of the aperture 20 relative to the peripheral bearing of the.

clamp lever on the bar.

The movement required on the clamp head is extremely slight to cause a positive and secure binding effect upon the supporting arm 8 and a relatively slight turning movement of the clamp screw 22 will exert sulficient pressure on the extremitylO to hold the arm in any position required. The arm may be as readily loosened as it may be set,

and thus frequent adjustments of the supporting roller may be made without undue inconvenience. It will be'readily seen that the block 5 r'iiaybe slidably removed alon a bar will be secured in any desire" position thereon, also that the clamp lever 17 may be positioned upon either side of said block by simply removing the outer cotter-pin 11 and withdrawing the angular e 1;- tremity 1-0 and reversing the clamp lever before replacing the angular extremity therethrough as before.

The device is very simple in its construction and is positive and reliable in its operation. It is strong and serviceable in its design and thoroughly adapted for the service for which it is intended.

From the foregoing description taken in connection with the accompainiing drawings the advantages of the construction and application of my in'iproved undercutting saw supports will be rtnidil apparent. but, while I have described the principle of operation of the invention t other with the devices which I non consider the best embodiment thereof, it will be lllltltl'FTtOOtl that the structures shown are merel illustrative, and that such changes may be made therein as will lie within the scope of the "following claims.

Having described my invention, what I claim, is:

1. An undercutting saw support, consisting in a bar adapted to be driven into a log, a block slidahle upon said bar, a cam-clamp mounted in said block provided with a lever extendin longitudinally of mid bar hrwiue a screw at its outer end hearing upon aid bar, and a swingable arni having a rotatable saw-supporting element at one end and pivotallv mounted at. its other end in said lilorlt. said arm-end extending through an eccentric aperture in said cam-clamp vcherehv the arm is retained in adjusted radial positions 2. An undercutting saw-support, eonsish ing in a bar, a block mounted upon said bar having a pair of apertured ears up n opposite sides of the bar. a s\\'in{1al)le arm provided with means to support a saw at one end and evtendine at its te end through said ears, a mini-clamp mounted hetxveen said ears and formed with an aperture through which said arm extendin register vcith said ear-apertares. raid clamp having a bearing upon one side of its aperture upon the bar, and hein; provided upon its opposite side with a lever, and a screw extending through said clamp-lever and bearing upon the bar.

ALFRED nit-inn 

